Parallel shielding and light control luminaire for fluorescent type lamps



Aug. 28, 1956 w. L. LIPSCOMB 2,761,053 PARALLEL SHIELDING AND LIGHT. CONTROL LUMINAIRE FOR FLUORESCENT TYPE LAMPS Filed Jan. 21, 1955 r2 Sheets-Sheet l INVENTOR.

WILLIS L. LIPSCOMB.

AGENTS.

8, 1956 w. L. LIPSCOMB 2,761,053

PARALLEL SHIELDING AND LIGHT CONTROL LUMINAIRE FOR FLUORESCENT TYPE LAMPS Filed Jan. 21, 1953 2 Sheets-Sheet 2 Fig.5.

AGENTS.

United States Patent 2,761,058 PARALLEL SHIELDING AND LIGHT CONTROL LUMJNAIRE FOR FLUORESCENT TYPE LAMPS Willis L. Lipscomb, San Diego, Calif. Application January 21, 1953, Serial No. 332,409 6 Claims. (Cl. 240-5111) The present invention relates generally to lighting equipment and more particularly to a parallel shielding and light control luminaire for fluorescent type lamps.

The primary object of this invention is to provide a suspended type luminaire which will produce a high degree of illumination at low cost.

Another object of this invention is to provide a luminaire which employs standard fluorescent tubular lamps therein.

Another object of this invention is to provide a luminaire in which the lamps are invisible from any viewpoint level with or below said luminaire in its suspended position.

Another object of this invention is to provide a luminaire which produces adequate and even illumination by indirect means.

Another object of this invention is to provide a luminaire having means to discourage the settling of dust therein.

Another object of this invention is to provide a luminaire which is easily cleaned While in its suspended position.

Another object of this invention is to provide a luminaire which is self-ventilating when in use so that heat generated by the lamps is quickly dissipated and the life of the lamps is greatly increased.

Another object of this invention, ancillary to the preceding objects, is to teach the best known mode of implementing the principles of the invention in carrying v the invention into actual practice.

Another object of this invention is to provide a luminaire which is adapted for fabrication from many different materials so that the choice of material canbe according to the dictates of availability and price considerations, the exact sizes and proportions being matters easily determined to suit particular conditions and needs.

Another object of this invention is to provide a luminaire which is inexpensive and practicable to manufacture.

Finally, it is an object to provide a luminaire of the aforementioned character which is simple, safe and convenient to operate, and which will give generally efficient and durable service.

With these and other objects definitely in View, this invention consists in the novel construction, combination and arrangement of elements and portions, as will be hereinafter fully described in the specification, particularly pointed out in the claims, and illustrated in the drawings which form a material part of this disclosure and wherein similar characters of reference indicate similar or identical elements and portions throughout the specification and throughout the views of the drawings, and in which: i

Fig. 1 is a perspective view of the luminaire in its suspended position;

Fig. 2 is a half transverse sectional view;

Fig. 3 is an enlarged fragmentary perspective view showing portions of the luminaire;

Fig. 4 is a fragmentary sectional view of a modified portion of the luminaire;

Fig. 5 is an enlarged fragmentary exploded view of portions of the luminaire; and

Fig. 6 is a half plan view of the luminaire, the view being broken to conserve space.

2,761,058 Patented Aug. 28, 1956 Referring to the drawings in detail, a base channel member is indicated by the numeral 10. The base channel member 10, substantially V-shape in cross section, extends longitudinally from end to end of my luminaire. The channel member 10 is continued to comprise inclined support walls 12 and the flanges 14 extending outwardly therefrom. The strengthening flanges 16 are also integral with the base channel member 10 and extend vertically from the flanges 14. A support channel 18 is positioned within the base channel member .10 and is coextensive in length therewith. The support channel 18 is provided with a flat horizontal bottom 20, on which is affixed the standard ballast 22 and like units. Inclined lateral flanges 24 are provided on the channel 18 and are secured to the walls 12 of the channel member 10. The upper channel member 26 is of inverted V-shape in cross-section and is provided with flat inclined support surfaces 28 on which are secured the lamp brackets 30. Indicated at 32 are the fluorescent type lamps used in my luminaire. The outer edges of the upper channel member 26 are extended to form inclined flanges 34, said flanges 34 abutting against the support walls 12 of the lower channel member 10 and being secured thereto.

Indicated at 36, 38, 40, 42, and 44 are a plurality of slats, said slats being transversely inclined at an acute angle to the horizontal and being disposed one above the other in stepped, parallel relationship and extending the whole length of my luminaire. A plurality of tubular spacers 46, 48, 50 and 52 are positioned between the slats 36, 38, 40 and'42 to maintain the relationship of said slats. These spacers have parallel ends acutely inclined to their longitudinal axes. The spacers 46, 48 and 50 have a concentric bore 51, while the spacers 52 have a threaded bore 54. Illustrated at 56 are tubular spacers which have one end normal to the longitudinal axis and the other end inclined similarly to the ends of the spacers 46, 48, 50 and 52. The hexagon-headed bolts 53 are inserted downwardly through the bore 51 in the spacers 56, through the slats 36, 38, 40 and 42, which have appropriately positioned holes therein to receive said bolts, and through the intermediate spacers 46, 48 and 50. The bolts 58 are then threadably secured in the spacers 52,

, which are welded or otherwise secured to the upper surface of the slats 44.

The slats 36, 38, 40 and 42 have downwardly inclined terminal flanges 60 at each end as best shown in Fig. 5, said flanges 60 engaging in inclined slots 62 provided in retaining plates 64. The retaining plates 64 are sub stantially U-shaped in cross-section having flanges 66. End plates 68 are opposed, vertical flat plates shaped to conform closely to the general cross-sectional profile of my luminaire and having a top edge 70 approximately in alignment with the upper edges of the opposed slats 36. The end plates 68 have inwardly turned flanges 72 on all sides with the exception of the top edge 70. It will be inner surfaces of the end plates 68 forming the recesses 74, said recesses 74 housing the flanges 60 of the slats 36, 38, 40 and 42. i

The slats 44 are of diiferent construction from the slats 36, 38, 40 and 42 as best shown in Fig. 2 of the drawings. The slats 44 have one longitudinal edge turned downwardly, forming the inclined elements 76. r

The inclined elements 76 are extended to form the flanges 73, which are substantially parallel with the main portions of the slats 44. The inclined elements 76 have the longitudinal slots 80 therein and the integral reflectors 3 82 outwardly bent from the lower edges of said slots 80.

The slats 44 have the extensions 84 at each end, said extensions 84 being secured between the lower edges of the retaining plates 64 and the flanges 72 of the end plates 68.

My luminaire is suitably braced by the strengthening flanges 16, which are terminally secured to the upper surfaces of the slats 42. Additional bracing is provided by the channel-shaped brackets .86, which are secured to the inclined elements 76 of the slats 44 and to the inclined support walls 12 of the base channel member 10.

It will be evident on referring in detail to Figs. 1 and 2 of the drawings that the stepped and inclined disposition of the slats is such that the lower longitudinal edge of one slat is in horizontal alignment with the upper longituclinal edge of the slat immediately beneath said first mentioned slat. Thus from any viewpoint on or below the horizontal the lamps are invisible, and therefore no light produced by said lamps will be directly projected downwardly. Adequate illumination is provided, however, by reflection, since a large number of reflecting surfaces are presented by the slats, the flanges 78, the reflecting surfaces 82 and the under-surfaces of the base channel member 10. Typical examples of the light-reflective features of my luminaire are indicated in light line in Fig. 2 of the drawings. It will be obvious that the light will be reflected in all directions ensuring adequate, even illumination. Interreflected light is also indicated by arrows '77 and 79.

In many lighting fixtures of the closed bottom type, efliciency is often greatly impaired by the accumulation of dust caused by the passage of air currents across the top and downwardly into said fixtures. involve much cleaning time. In my luminaire, however, air currents are permitted to pass upwardly through the spaces provided between the slats 44 and the base channel member 10. The complete exposure of the lamps 32 assists in the dissipation of heat by upwardly moving air currents through the spaces between the slats 44 and between the lowermost slats and the base channel member 10. In addition, the upward and outward inclination of the slats assists in inducing the air currents away from the lamps 32.

It will be obvious therefore that the possibility of dust Dust removal and also lamp replacement are easily and quickly eflected due to the accessibility afforded by the open construction of my luminaire.

Fig. 4 shows in detail a modification of the preferred form of slats employed in my luminaire. A modified slat is indicated at 88 in transverse cross-sectional form having an upwardly turned flange 90 along its outer edge and a downwardly turned flange 92 along its inner edge. The flanges 90 and 92 are provided to give added strength to the slats preventing warpage or distortion.

The operation of this invention will be clearly comprehended from a consideration of the foregoing description of the mechanical details thereof, taken in connection with the drawings and the above recited objects. It will be obvious that all said objects are amply achieved by this invention.

Further description would appear to be unnecessary.

It is understood that minor variation from the form of the invention disclosed herein may be made without departure from the spirit and scope of the invention, and that the specification and drawings are to be considered as merely illustrative rather than limiting.

I claim:

1. In an indirect lighting fixture, a frame including an elongated channel member having substantially vertical end plates, a second channel member secured in inverted relationship with said first-mentioned channel member, whereby a compartment is defined between said first and Many such cases i second-mentioned channel members, a third channel member secured within said compartment and having ballast and like equipment secured thereto, lamps operatively mounted on said second-mentioned channel member, a plurality of inclined elongated slats secured to said frame in spaced relationship at either side of said lamps, ventilating openings between the lowermost slats and said channel member to discourage the accumulation of dust therein and to cool said lamps.

2. A frame for a lighting fixture comprising: Abase channel member having a pair of opposed upwardly extending walls; said walls having upwardly extending flanges; a support channel within said base channel member and parallel therewith and having longitudinally extending lateral flanges secured to said walls; an upper, inverted channel member parallel to said base channel member and having downwardly extending lateral flanges secured to said walls, whereby a compartment is provided between the support channel and said upper channel member; end plates secured to and capping the ends of said channel members; said end plates having laterally extending portions at the sides of said channel members; and slat supporting means on said laterally extending portions.

3. A frame according to claim 2 wherein said slat supporting means comprises slat-retaining plates disposed vertically adjacent the inner faces of said end plates; said slat-retaining plates having a plurality of slotted portions; and a plurality of slats extending between said slat-retaining plates and terminals secured in the slots of said slotted portions.

4. A fixture according to claim 3 wherein said slats have terminal flanges, and said slat-retaining plates have lateral flanges abutting said end plates whereby said slatted portions are spaced from said end plates to ac commodate said terminal flanges of the slats.

5. A frame according to claim 2 wherein said slat supporting means comprises slat-retaining plates disposed vertically adjacent the inner faces of said end plates; said slat-retaining plates having a plurality of slotted portions; and a plurality of slats extending between said slat-retaining plates and terminally secured in the slots of said slotted portions; said slats including a pair of lower slats each having an inclined portion extending toward said base channel member, said inclined portions having slots; and a reflector fixed adjacent to and below said slots to reflect light onto the lower surface of said base channel member.

6. A frame according to claim 2 wherein said slat supporting means comprises slat-retaining plates disposed vertically adjacent the inner faces ofsaid end plates; said slat-retaining plates having a plurality of slotted portions; and a plurality of slats extending between said slat-retaining plates and terminally secured in the slots of said slotted portions; said end plates having peripheral flanges engaging the ends of said base channel member and extending therebeyond; and said slats including a pair of lower slats having terminal portions engaged between the lower ends of said slat-retaining plates and the adjacent portions of said peripheral flanges.

References Cited in the file of this patent UNITED STATES PATENTS 1,193,191 Ritter Aug. 1, 1916 1,538,110 Hartmann May 19, 1925 1,876,667 Gunnison Sept. 13, 1932 1,918,455 Doane July 18, 1933 1,978,251 Doane Oct. 23, 1934 2,480,301 Moretz Aug. 30, 1949 2,510,346 Nitardy June 6, 1950 2,545,058 Walsh Mar. 13, 1951 2,567,779 Mitchell Sept. 11, 1951 2,703,360 Lipscomb Mar. 1, 1955 

